Guilherme Santos Silva > Abreu Advogados > Lisbon, Portugal > Lawyer Profile

Abreu Advogados
Av. Infante D. Henrique, 26

Work Department

Litigation and Arbitrarion Law, Corporate and M&A Law, Criminal. Sanctions and Compliance Law, Restructuring and Insolvency Law.




Guilherme Santos Silva is a Partner and has been with Abreu Advogados since 2004 working primarily on matters related to commercial litigation and arbitration, commercial law, corporate, telecommunications, energy and maritime and transportation law.

He focuses particularly on issues related to international and multi-jurisdictional commercial litigation, working on national and international judicial and arbitration proceedings. Concurrently, he advises national and international companies on corporate and commercial law matters, providing assistance, on an ongoing basis, on the legal aspects of the companies’ day to day operations.

Additionally, he has led several cases related to construction, sales, mortgages, seizures and enforcement of debt on ships and airplanes and providing assistance throughout the respective litigation proceedings.

His work extends to Angola, where he works on investment operations and partnerships with Angolan firms, primarily in the areas of telecommunications and energy (Oil & Gas). He has been supporting the relationship with Abreu Advogado’s international lawyers in Angola, both in the area of commercial advisory and judicial and arbitration litigation.

He also has a special relationship with training, having been an assisting professor at Moderna University Faculty of Law, Lisbon for 15 years (1992 to 2008) and actively continues to provide training on matters related to his practice, specifically arbitration and maritime and transportation law.

Over the past year he has supported large international litigation proceedings linked to multiple jurisdictions, such as, the United Kingdom, Saudi Arabia, China, Switzerland, Angola, Germany, France, Israel, Brazil, Italy and Holland in addition to Portugal.


Portuguese, English, French and Spanish.


Portuguese Bar Association.
International Bar Association.


Law degree from the Portuguese Chatholic University Faculty of Law (1991).

Lawyer Rankings

Portugal > Transport

Clients in the aviation, maritime, and wider transport industries routinely turn to Abreu Advogados for assistance in a wide range of matters, from corporate and financing transactions, to trade and environmental issues. The ‘prompt and capable’ team is co-led by dispute resolution specialist Guilherme Santos Silva, Pedro Alves Da Silva, and Nuno Luís Sapateiro. Alves da Silva’s strength lies in M&A, corporate law, and commercial contracts, while Luís Sapateiro possesses over 15 years’ experience of acting for insurance companies and airlines aviation in major domestic and international transactions.

Portugal > Dispute resolution

The ‘hands-on, pragmatic and very proficient’ dispute resolution team at Abreu Advogados represents clients in civil and commercial matters before judicial courts and arbitral tribunals. Working in tandem with its offices in Lisbon, Porto and Funchal, the practice provides nationwide coverage, and fields strong credentials in international arbitration proceedings. With over 20 years’ experience, seasoned mediator and arbitrator Alexandra Nascimento Correia leads the team alongside Guilherme Santos Silva, who handles civil, commercial and transportation disputes, with a focus on domestic and cross-border proceedings. Teresa Anselmo Vaz‘s sector-specific expertise spans the healthcare, life sciences and pharmaceutical industries, while Teresa Brito da Silva is active in commercial and corporate litigation. Gonçalo Malheiro‘s strong litigation practice covers criminal litigation and contractual disputes. Focusing on Portuguese-speaking countries, André Pereira da Fonseca is experienced in cross-border arbitration and litigation.

Angola > Foreign firms

The Angola practice of Abreu Advogados often handles M&A, finance, and tax matters across the oil and gas as well as infrastructures sectors. Guilherme Santos Silva, Manuel Santos Vítor, and João Bravo da Costa lead the practice, Santos Silva advises oil and gas and aviation clients on corporate matters and dispute resolution, while Santos Vítor stands out in the energy and mining sectors. Bravo da Costa brings expertise in energy M&A, international trade, and financial matters.